Some users have had problems in former 12.05 release with their site being inaccesible after installing the plugin. Very sorry for that !
It all seemed to be part of the same problem with the capabilities.php file that is discussed here: http://wordpress.org/support/topic/fatal-error-call-to-undefined-function-wp_get_current_user-4?replies=32
But, NO, that was not the correct problem, nor the solution.
This update fixes it the correct way.
I used the wp_loaded hook to init the plugin, then, check whether the user can "erase themes" which is an Admin capability only, so the plugin only works if you are logged in as an admin, and starts only after all of WP is loaded, thus avoiding using the capabilities.php functions before pluggable.php has been loaded. So, no need to modify the capabilities.php file to "fix" an unexisting bug, as I was suggesting in the former version.
Hopefully there won't be more serious problems !
If anybody is interested in the development of the plugin, I'd like to know how to add more users to the repository as contributors, so that anyone interested may commit patches or release new versions. I'm quite new at subversion and WordPress...
Please, all feedback is welcome, and I sincerely hope this won't break your site anymore...